Members who have donated towards server costs
Join Date: Aug 2005
Location: Okehampton, southwest England
OK guys & ladies, here goes. This is how I have done my fork seals in the past. It is not quite the same as the shop manual method but it works for me. Each time I have replaced them they have lasted nearly 30,000 miles. My bike has covered in excess of 75,000 miles now without major problems. (except the dreaded driveshaft splines but that's another story) I have found the only "special tools" I need are a length of pipe (no sharp edges!) that just fits over the fork tube (for driving the seals into place) and a thin wooden rod tapered at one end to stop the damper rod from turning when undoing the bottom bolt. First obtain a new set of genuine Kawasaki seals & also new dust seals, I have found it very difficult to remove these without damaging them, they also sometimes rust underneath where the water gets past them. (Plenty of water here in England!) Also, having gone to all the trouble of replacing the main seals, you may as well replace the dust seals while you have everything apart.
Place bike on centerstand, place a jack (with a piece of wood on top to protect the sump) under the engine & raise the front of the bike just enough for the front wheel to come off the ground. Remove the wheel, fender, calipers & brake hose guides. Remove the plastic caps on the top of each fork. I have found it best to remove & work on one side at a time (as tonyfan70 says). That way, the yokes have no chance of going out of line. Loosen the pinch bolts on one side & carefully slide the fork assembly out of the yokes. Place the whole assembly in a vice using soft jaws to protect the aluminium, clamp it up on the caliper mounts & don't overtighten the vice! Release any air in the forks by pushing down the top valve (if fitted) althought if the seals are shot there probably won't be much pressure in there anyway. Place a 6" extension bar into a half inch socket and place the socket over the valve and push down to expose the thin snap ring that holds the top in place. If the cap is stuck, give the end of the extension bar a sharp tap with a soft hammer or a piece of wood. While holding the cap down, hook out the snap ring with a thin screwdriver and let the spring pressure lift up the cap. Remove the cap, spacer, washer & spring & take note of the order they come out in. Take the whole assembly out of the vice for a moment & pour the fork oil out into a container, it will probably be very dirty & look a bit like milk if enough water has got in. Place the assembly back in the vice &, using a good quality allen wrench, undo the bottom bolt. If the bolt keeps turning but doesn't seem to want to come out the damper rod is turning inside & needs to be held as follows. Using a piece of thin wood that has been filed to a taper at one end (a thin broom handle will do) push it down into the tube until it pushes against the bottom. Hold it tight & the bolt should undo without a problem. Next, pry off the dust seal & slide it up the tube & off the top. Remove the snap ring that retains the oil seal. Now you need to pull up sharply on the tube to remove the seal, sometimes 2 or 3 goes may be needed but it WILL come out. Once the seal has popped out of it's place you can slide it up the tube & remove it. What you do now is up to you. You can either start putting the assembly back together or (recommended) strip the tube out of the stanchion & give the components a thorough clean. If you decide to strip the assembly, make a careful note of how it all came out so you can put it all back exactly as it should be. Oil everything as you put it back together. Remember, one mistake could seriously upset things as far as handling goes! (Or worse!) When you are ready to fit the new seals proceed as follows. Make sure the ouside of the fork tube is clean, apply a thin film of fork oil to the outside to lubricate the new seal & very gently slide the new seal down over the tube. Now you need your piece of pipe I mentioned earlier. I use plastic pipe that I got from the scrap bin where I work (can't remember the exact size, will let you know later). It just fits over the tube & is exactly the same size as the outer edge of the seals. It is also longer than the tube so that it can be tapped from the top. Place the pipe over the tube & gently tap the seal into place using a soft mallet on the other end of the plastic tube. Replace the snap ring. Now slide the new dust seal over the top. I use a very thin bead of silicone sealant underneath the outer edge of the dust seal which will stop water getting under the seal & rusting the metal reinforcing ring underneath. Don't apply too much silicone or it will go over the fork tube when you tap it down & you don't want to do that. Tap it gently into place & wipe off any excess sealant that gets squeezed out of the edge. Now you can replace the bottom bolt & tighten it to the correct torque (14.5 ft/Ibs). Use a new copper washer if necessary. If the damper rod turns, use your wooden rod to hold it still like you did earlier when you undid it. Pour 362ml of new fork oil in the top, replace the spring, washer & spacer then replace the cap & snap ring & you're done! Wipe off any excess fork oil from the tube & any you spilled anwhere else - you don't want the stuff getting anywhere near the brakes! Replace the fork assembly in the yokes, tighten the pinch bolts & repeat the whole process on the other fork. You can then replace the wheel, fender & calipers etc & the jobs done. Double check everything is in place & tight before you ride the bike & admire your (hopefully) nice dry forks!
I hope this procedure makes sense - if anyone thinks I have missed anything, or needs more information then please let me know. I am also always open to suggestions on anything that might make the job any easier!
Take care & ride safe!
1991 BMW K1100LT
1980 Suzuki GS1000G
Last edited by Ernie; 05-03-2006 at 03:32 PM.